I very much appreciate how this version, while different, mimics the action advantage mechanics of the hero version (Boromir).
Thematically, the first ability fits great with the defender of the Hobbits role played out in the saga expansions where this card emerged. Clearly it can be of great use in low threat decks, but often those are designed around not engaging a lot of enemies or participating in a lot of combat. However I do like the parallel to the oft equipped Gondorian Shield on the hero version. Other standard boosting effects could be considered: Arwen Undómiel, Narya, Behind Strong Walls and Blade Mastery, For Gondor!, Raiment of War play well with his ability to counterattack. Round Shield is also particularly good to keep him in the fight. (I'm omitting discussing fringe or janky shenanigan cases mostly enabled by Sword-thain).
As alluded to, it's the second ability that gets the most mileage personally; as long as he can keep taking damage he can keep readying and defending (he's almost an honorary Ent). Obviously, you're going to need healing, and lots of it. This pairs great with Elrond and any cheap repeatable healing, particularly Warden of Healing, Imladris Caregiver, or even Glorfindel. Hopefully, with Elrond around, you even got him into play via Vilya.
Some fun you can have: Ent Draught, Raiment of War and abusing Vigilant Guard, particularly good with Beorn. The rarely used Sword of Morthond is a great target for him as well.
If a quest has the potential to swarm you with a lot of medium hitting allies, Boromir can be a great defensive solution, especially if you carefully plan out the sequence of your defenses and keep sending him to the House of Healing. He certainly passes the stat points to cost ratio test. Too bad he can't be in play with a Visionary Leadership Boromir.